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	<title>Document</title>
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    <table>
    	<tr>
      <th>班级</th>
      <th>学生数</th>
      <th>平均成绩</th>
    </tr>
    <tr>
      <td>一班</td>
      <td>30</td>
      <td>89</td>
    </tr>
    <tr>
      <td>二班</td>
      <td>35</td>
      <td>85</td>
    </tr>
    <tr>
        <td>三班</td>
        <td>32</td>
        <td>80</td>
    </tr>
    </table>
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	<table>
    <tr>
    	<td colspan="3">1</td>
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    <tr>
    	<td rowspan="2" colspan="2">4</td>
    	<td>5</td>
    </tr>
    <tr>
    	<td>7</td>
    </tr>
    <tr>
    	<td>10</td>
    	<td>11</td>
    	<td>12</td>
    </tr>
    </table>
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